US3116341A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for recovering methylnaphthalenes
Assignee: United States Steel Corp
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Filing: 1961-05-04
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Granted: 1963-12-31
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Expires: 1981-05-04
Abstract
No abstract record available.
Inventors
- 👤 Chester S Sheppard
- 👤 Clair J Warning
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:59
CPC Classifications
C; C07; C07C; C07C15/00; C07C15/20; C07C15/24; C07C5/00; C07C5/22; C07C5/27; C07C5/2729; C07C5/2732; C07C5/2735; C07C7/00; C07C7/005; C07C7/12; C07C7/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
155 words
A METHOD FOR RECOVERING 2-METHYLNAPHTHALENE FROM AN ACID-WASHED, COAL TAR FRACTION BOILING BETWEEN ABOUT 230* AND 260*C. AND CONTAINING METHYLNAPHTHALENES IN ADMIXTURE AS 1-METHYLNAPHTHALENE AND 2-METHYLNAPHTHALENE, WHICH CONSISTS IN DISTILLING SAID COAL TAR FRACTION AT ATMOSPHERIC PRESSURE AND REMOVING THEREFROM MATERIAL BOILING BELOW ABOUT 237*C., FURTHER DISTILLING THE REMAINING FRACTION BOILING ABOVE ABOUT 237*C., BETWEEN ABOUT 1 MM. AND 250 MM. MERCURY ABSOLUTE PRESSURE AND COLLECTING A FRACTION CONTAINING ABOUT 90 PERCENT METHYLNAPHTHALENES, PASSING SAID COLLECTED FRACTION THROUGH A CHROMATOGRAPHIC ADSORBENT CHOSEN FROM THE GROUP CONSISTING OF SILICA GEL, ALUMINA AND ACTIVATED CLAY, COOLING PURIFIED METHYLNAPHTHALENES EFFLUENT FROM SAID CHROMATOGRAPHIC ADSORBENT TO BETWEEN ABOUT +5* AND -25*C. AND SEPARATING CRYSTALS OF SUBSTANTIALLY PURE 2METHYLNAPHTHALENE FROM MOTHER LIQUOR, HEATING SAID MOTHER LIQUOR AND HYDROGEN TO A VAPOR, PASSING SAID VAPOR INTO CONTACT WITH A SILICA-ALUMINA CATALYST AT AN ISOMERIZATION TEMPERATURE BETWEEN ABOUT 375* AND 505* C. AND RECYCLING THE RESULTING ISOMERIZED PRODUCT TO SAID COOLING STEP.
Claim 2
Independent Claim
155 words
A METHOD FOR RECOVERING 2-METHYLNAPHTHALENE FROM AN ACID-WASHED, COAL TAR FRACTION BOILING BETWEEN ABOUT 230* AND 260*C. AND CONTAINING METHYLNAPHTHALENES IN ADMIXTURE AS 1-METHYLNAPHTHALENE AND 2-METHYLNAPHTHALENE, WHICH CONSISTS IN DISTILLING SAID COAL TAR FRACTION AT ATMOSPHERIC PRESSURE AND REMOVING THEREFROM MATERIAL BOILING BELOW ABOUT 237*C., FURTHER DISTILLING THE REMAINING FRACTION BOILING ABOVE ABOUT 237*C., BETWEEN ABOUT 1 MM. AND 250 MM. MERCURY ABSOLUTE PRESSURE AND COLLECTING A FRACTION CONTAINING ABOUT 90 PERCENT METHYLNAPHTHALENES, PASSING SAID COLLECTED FRACTION THROUGH A CHROMATOGRAPHIC ADSORBENT CHOSEN FROM THE GROUP CONSISTING OF SILICA GEL, ALUMINA AND ACTIVATED CLAY, COOLING PURIFIED METHYLNAPHTHALENES EFFLUENT FROM SAID CHROMATOGRAPHIC ADSORBENT TO BETWEEN ABOUT +5* AND -25*C. AND SEPARATING CRYSTALS OF SUBSTANTIALLY PURE 2METHYLNAPHTHALENE FROM MOTHER LIQUOR, HEATING SAID MOTHER LIQUOR AND HYDROGEN TO A VAPOR, PASSING SAID VAPOR INTO CONTACT WITH A SILICA-ALUMINA CATALYST AT AN ISOMERIZATION TEMPERATURE BETWEEN ABOUT 375* AND 505* C. AND RECYCLING THE RESULTING ISOMERIZED PRODUCT TO SAID COOLING STEP.
References Cited (Backward Citations)
US2920115A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1966-12-30 | 1967-07-01 | 1967-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-12-30 | 1971-07-01 | 1971-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-12-30 | 1975-07-01 | 1975-12-31 | $7700.00 | Window Closed / Lapsed |